<!DOCTYPE html>
<html>
<head>
	<title></title>
	<style type="text/css">
		.rr{
			font-size: 30px;
			font-weight: bold;
			color:red;
		}
		.bb{
			border:1px solid blue;
			width:100px;
		}

	</style>
</head>
<body>
	<span class='rr'>hello</span>
	<span>css</span>
	<div class='rr bb'>haha</div>
	<div class='bb'>hehe</div>


</body>
</html>